Hooking up the ground and Remote wire.

So I recentley purchased and Amp but when I turn it on the protect light blinks on and off. Which either means that there is a short in on of the connects, the ground is making proper contact or the amp is broken. I know its not broken because I tried it on a friends car and it works fine. So Im think its the gorund and was wondering what the best spot to put it on a 1998 Honda Accord would be. Also my car doesn't have the standard blue remote cable and I was wondering If I would be able to connect it to the Radio Switch 12v cable. I am currently connection it to a car adapter that made which is connect via the cigarette light thing.